1. Field of the Invention
This invention relates to a method for improving the average quench rate as well as the upper ribbon surface texture and ribbon edges during melt-spinning of metallic ribbons.
2. Description of the Prior Art
The ambient atmosphere in which chill-block melt-spinning of metallic ribbons is conducted apparently has little, if any, effect on the upper ribbon surface texture and on ribbon edge definition if processing is conducted within the confines dictated by U.S. Pat. No. 4,144,926(H. H. Liebermann, 1979). However, undesirable molten alloy puddle fluctuations may be caused by corresponding fluctuations in the melt jet prior to impingement on the moving substrate surface and by impact-induced fluctuations caused by various kinds of imperfections in the substrate surface. The upper ribbon surface topography may consequently have a "ripply" texture which is particularly prominent during the fabrication of metallic ribbons greater than 3/4mm wide.
Therefore, it is an object of this invention to provide a new and improved method for chill-block melt-spinning metallic ribbons.
Another object of this invention is to provide a new and improved method for increasing quench rate during chill-block melt-spinning.
Still another object of this invention is to provide a new and improved method for reducing the upper surface texture and improving edges of chill-block melt-spun metallic ribbon.
A further object of this invention is to provide, for example, a gas stream confluent with and surrounding the molten alloy jet so as to bear down upon the molten alloy puddle near the point of melt jet impingement on the moving substrate in order to improve heat transfer and to eliminate adverse gas boundary layer effects on ribbon geometry. Another object of the gas jet confluent with the melt is to minimize melt-atmosphere reaction and to reduce the upper ribbon surface texture and improve edge definition of chill-block melt-spun metallic ribbons during manufacture thereof.
Other objects of this invention will, in part, be obvious and will, in part, appear hereinafter.